Research On Quantum Communication And Qkd Network

QKD (Quantum Key Distribution) is a subject related with quantum mechanics and information science. As it can realize unconditional security in communication, the potential applications could be in military, commercial business and other confidential areas.This thesis is about the research on practical QKD systems and quantum network. The organization of the thesis is as follows:First, we outline the principle on QKD; introduce the single photon protocol and continuous-variable protocol, and analyze the problems on the application of QKD.Second, we design a two-way QKD system based on phase encoding, introduce the principle, and finally analyze the experimental result.Third, we conclude several ways to realize QKD network, illustrate the related problems on the realization. We design a 3-node QKD network in control of optical switch, and introduce the principle and results.Forth, we introduce the circuit principle in the QKD system, introduce the 2 electric chips and the related problems, and explain how to design the PCB board.